Element Test using D_MOD2 PEER 2G02

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Element Test using D_MOD2PEER 2G02

• By Dr. Neven Matasovic

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• I completed my analysis for the PEER 2G02 second
  assignment. As you know, input in D-MOD is an
  acceleration time history. D-MOD can not accept
  shear strain (or stress) as an input and it does
  not allow for specification of initial static
  shear stress (strain). The only way to check
  what D-MOD does in terms of stress-strain
  behavior is to excite one element by a series of
  acceleration time histories (as you provided in
  terms of shear strain time histories).
  Therefore, I
• 1.      converted the shear strain time histories
  you provided into the acceleration time
  histories. I did that by arbitrarily assigning
  time step of 0.02 seconds and peak amplitude of
  approximately 0.9 g to each shear strain time
  history you provided and
• 2.      arbitrarily assigned a small amount of
  viscous damping (approximately 0.4) mass and
  stiffness to a single element and applied the
  above described, converted time histories to a
  (compliant) base of the model.
• 3.      run the analysis using the modified MKZ
  model and monitored the results in terms of shear
  stress and shear strain time histories.
• Please note that, in fact, I did a non-linear
  single-degree-of-freedom system analysis. The
  results of my evaluation follow plots of
  acceleration time histories used in the analyses.
  Please also note that I was able to analyze only
  spreadsheet steps 1 and 3 as D-MOD does not
  allow for specification of initial static shear
  stress (strain).
• The results of my evaluations show that
  stress-strain model embedded in D-MOD strictly
  follows the Masing rules.
• As always, the D-MOD input/output files and
  related spreadsheets are available. Please let
  me know if you require them,or anything else
  related to this exercise.
• Sincerely,
• Neven Matasovic

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